Father denied for gun purchase & permit, was able to purchase twice priorto

[SouthPhilly]

My father was charged in 1982 with theft and unlawful taking and was sentenced to one year probation and was a misdemeanor-1 charge.

In 1985, he legally purchased a .357 magnum, after being approved, from an authorized dealer, The Firing Line gun shop in Philadelphia, Pennsylvania.

In 1997, he legally purchased a 9mm Taurus from Mike and Kate's Sporting Goods Store, after being approved, in Northeast Philadelphia, Pa.

In 2008, he attempted to purchase a Glock .45 ACP and was denied.
In 2010, he applied for a LTCF in Pennsylvania, through Philadelphia and was denied.

The state police officer told him he was denied because of the misdemeanor-1 charge of 1982. The officer told him both purchases would have been illegal and should have been denied, therefor he is in possession of an illegal firearm, the 9mm Taurus, which he was legally approved for.
The officer said my fathers misdemeanor-1 comes under a federal law and over rules anything else. He said even though it was a misdemeanor-1, they go by what the maximum sentence COULD have been given.

Is this correct? My father nor any workers from our local shops have been able to explain this.