Rоnald E. Purham appeals from a final judgment entered in the District Court 1 for the Eastern District of Missouri upon a jury verdict finding him guilty of forcibly robbing a postal employee of United States Post Office keys. The district court sentenced appellant to twenty-five yeаrs imprisonment. For reversal appellant argues that the district court erred in denying (1) his motion to dismiss the indictment on the grounds of preindictment delay, (2) his motion for expert witness services at government expense, and (3) his motion to suppress a preindictmеnt lineup identification. For the reasons discussed below, we affirm the judgment of the district court.
On July 28, 1981, while investigating a consumer complaint, a postal employee was robbed by two men, one of whom was armed with a sawed-off shotgun. The robbers took the рostal employee’s cash, jewelry, credit cards, and six United States Post Office keys. The keys opened a registered mail vault where mail valued at $1,000 or more was kept.
The postal employee immediately reported the robbery and gave a description of the robbers to local police and federal postal inspectors. While canvassing the neighborhood where the robbery took place, one of the investigating federal postal inspectors discovеred a witness who had seen two men at the site of the robbery immediately before and after the robbery. The witness had not seen the robbery but his description of the two men closely matched the description given by tfie victim. The witness identified appellаnt by name as one of the two men he had seen and provided appellant’s address.
The day after the robbery the federal postal inspector and local police went to the address that had been provided by the witness. The federаl postal inspector recognized appellant from the descriptions given by the victim and by the witness but decided not to question appellant that day. The federal postal inspector testified that he thought appellant was intoxicated at that time.
The next day, July 30, 1981, the federal postal inspector and local police returned to the address and knocked on the door. Appellant’s mother and sister answered the door. One of the investigating officers asked to speak with appellant. The women permitted them to enter the residence. As the investigating officers entered, they saw appellant coming down the stairs. Shortly thereafter appellant was arrested by the local police. The victim later identified appellant in a lineup as the robber with the shotgun.
Later that same day state authorities charged appellant with armed robbery and placed him in jail to await trial on that charge. One year later, on July 30, 1982, appellant filed a motion to dismiss with prejudice for failure to grant a speedy trial. The state trial court granted appellant’s motion to dismiss and released him from custody in August 1982.
On September 16, 1982, a federal grand jury indicted appellant for the same transaction that was the subject оf the state *453 prosecution and charged him with forcibly robbing a postal employee of United States Post Office keys, in violation of 18 U.S.C. § 2114. Appellant was arraigned on November 12, 1982. Following denial of pretrial motions for dismissal, expert witness services and suppression of identification testimony, trial began on January 3, 1983, and the jury returned the guilty verdict the next day. This appeal followed.
1. Preindictment Delay
Appellant first argues that the district court erred in denying his motion to dismiss the indictment for prosecutorial delay. Appellant argues that the delay of more than a year between the date of the crime (July 1981) and the federal indictment (September 1982) substantially prejudiced his defense. Appellant argues that crucial defense witnesses became unavailable during the рeriod of delay. In support appellant submitted an affidavit from an investigator from the local public defender’s office who had assisted in preparing appellant’s defense in the state prosecution. This affidavit stated in pertinent part: “[C]ertain witnesses named by the defendant as being critical to his defense and who were available at the time the original State charge was pending are currently unavailable or unable to be found.”
Generally, post-indictment or post-acсusation delay may violate the constitutional or statutory speedy trial guarantees; however, preindictment delay may violate the due process clause.
United States
v.
Lovasco,
Assuming for the purposes of argument that the delay of more than a year betweеn the date of the crime and the filing of the federal indictment was unreasonable,
2
a careful review of the record convinces us that the district court correctly found that appellant did not demonstrate actual prejudice. Appеllant has relied solely on the admittedly “real possibility of prejudice inherent in any extended delay: that memories will dim, witnesses become inaccessible, and evidence be lost.... [T]hese possibilities are not in themselves enough to demonstrate thаt [appellant] cannot receive a fair trial and to therefore justify the dismissal of the indictment.”
United States
v.
Marion,
Nor was there any proof that the delay in bringing the federal indictment was an intentional device to gain tactical advantage over appellant. Appellant does not allege that the deference of the federal authorities to the state prosecution was “purposefully designed so as to give the government ‘two bites at the apple.’ ”
United States v. Mejias, 552
F.2d 435, 443 (2d Cir.),
cert. denied,
II. Expert Testimony
Appellant next argues that the district court erred in denying his motion for expert servicеs. Appellant contends that he should have been allowed expert testimony in the form of a criminologist who would have testified about the inherent inaccuracies of eyewitness identification. Specifically, appellant challenges the district court’s rejection of his request for government funds under 18 U.S.C. § 3006A(e) to pay for preparation of a testimonial offer on the subject of scientific evidence relating to perception and memory of eyewitnesses.
Admission or exclusion of expert testimony is a matter within the sound discretion of the district court.
United States v. Oliver,
III. Preindictment Lineup Identification
Appellant also argues that the district court erred in admitting the preindictment lineup identification. Appellant contends the evidence should have been suppressed for several reasons. First, he argues that because he was denied his constitutional right to counsel at the preindictment lineup identification, the evidence is not admissible against him. Second, he contends that the identification is inadmissible because he was arrested at home by a police officer who did not have an arrest or search warrant or consent to enter. Finally, appellant argues that his warrantless arrest was unlawful because it was not based on probable cause and thus the subsequent preindictment lineup identification is “poisonous fruit” and should have been suppressed. We find all three arguments without merit.
A. Right to Counsel
It is firmly established that a defendant’s sixth or fourteenth amendment right to counsel attaches only after adversarial judicial proceedings have been initiated.
United States v. Wade,
*455 B. Consent to Enter
Warrantless arrest in the accused’s home is not permissible absent exigent circumstances or consent to enter.
Payton v. New York,
C. Probable Cause
Probable cause exists where “ ‘the facts and circumstances within (the arresting officers’) knowledge . .. were sufficient to warrant a prudent [person] in believing that the (suspect) had cоmmitted or was committing an offense.’ ”
United States v. Everroad,
Our review of a district court’s determination of probable cause for arrest is limited by the clearly erroneous standard.
E.g., United States v. Wentz,
Accordingly, the judgment of the district court is affirmed.
Notes
. The Honorable William L. Hungate, United States District Judge for the Eastern District of Missouri.
. Arguably only the two months delay between the dismissal of the
state
charge and the filing of the
federal
indictment should be attributable to the
federal
government.
Cf. United States v. MacDonald,
