the river card as bad as my opposition

[joeboss]

sb is paying for my tuition other guy is tag
whats your river play?
Party Poker 15/30 Hold'em (5 handed)

Preflop: Hero is UTG with A/images/graemlins/spade.gif, Q/images/graemlins/diamond.gif.
<font color="CC3333">Hero raises</font>, <font color="CC3333">MP 3-bets</font>, Button folds, <font color="CC3333">SB caps</font>, BB folds, Hero calls, MP calls.

Flop: (13 SB) 2/images/graemlins/spade.gif, K/images/graemlins/spade.gif, J/images/graemlins/heart.gif <font color="blue">(3 players)</font>
<font color="CC3333">SB bets</font>, Hero calls, MP calls.

Turn: (8 BB) 8/images/graemlins/spade.gif <font color="blue">(3 players)</font>
<font color="CC3333">SB bets</font>, Hero calls, <font color="CC3333">MP raises</font>, <font color="CC3333">SB 3-bets</font>, Hero calls, MP calls.

River: (17 BB) J/images/graemlins/spade.gif <font color="blue">(3 players)</font>
SB checks, <font color="CC3333">Hero bets</font>, <font color="CC3333">MP raises</font>, SB calls, Hero calls.

Final Pot: 23 BB

[Zele]

Why not raise the flop?

I'd play the river the same way, given MP a tag.