As a legislator he was noted for being strongly pro-life due to his being a devout Roman Catholic.
He unsuccessfully ran for Mayor of Providence in a special election in 1984 following Cianci ouster.
The Convention succeeded in producing a neutral rewrite of the 1843 Rhode Island Constitution and proposing several amendments which were voted on in November 1986.
In his legal career, he was the senior partner of the law firm of McKenna, Greenwood & Feinstein in Providence.
McKenna's last forays into politics were defeats in the Democratic primaries of 2014 and 2016 for state senator for District 17, representing the towns of North Smithfield and Lincoln.