A Maryland state trooper whose duties included enforcing state trucking regulations has been found guilty by a police trial board of accepting favors from Excavation Construction Inc., a Prince George's County-based heavy construction firm which operated a huge fleet of dump trucks on Maryland highways.

The trial board ruled unanimously last month that Lt. Charles Earl Robinson, a state trooper for almost 20 years, was guilty of soliciting and receiving favors including cash for a softball team and free tickets for himself and his friends to a sky suite in the Capital Centre from the firm.

Excavation Construction and its general manager were indicted in the District of Columbia last August and charged with bribing a D.C. Superior Court judge who dismissed hundreds of thousands of dollars worth of fines against the company.

The trial board found Robinson guilty of 10 or 13 charges against him, most of which centered on a pattern of favors by Excavation Construction during the 1970s. The board, whose recommendations must be acted on by the superintendent of the State Police, recommended dismissal for Robinson.

Among other things, the charges against Robinson included allegations that the state police officer had solicited and received thousands of dollars for a softball team -- Robbie's Raiders -- named after Robinson and made up mainly of state troopers. Robinson had retained part of the money for his personal use, according to the charges.

The board also found that Robinson had accepted free tickets to the Capital Centre and free food and drink at sporting events there from the powerful construction company.

According to testimony at the five-day hearing in September, the state policeman had called a colleague in the state police who had been citing Excavation Construction trucks for improper registration and asked him to "ease off."

The case, which was prosecuted by assistant Maryland attorney general Stephen Schwenning, was brought to the trial board after an internal investigation by the State Police. Another trooper, Sgt. David S. Miller, is scheduled to go before the trial board Oct. 20 on similar charges involving Excavation Construction.

The firm, a once-powerful construction with millions of dollars in Metro contracts and other work, has been the center of several law enforcement investigations over the last three years, including a grand jury investigation in D.C., a grand jury investigation in Baltimore and the investigation into the murder of the president of one of the firm's subsidiary companies.